Commit Graph

467 Commits

Author SHA1 Message Date
Adrian Prantl 74a835cda0 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

This reapplies r289902 with additional testcase upgrades.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

llvm-svn: 289920
2016-12-16 04:25:54 +00:00
Adrian Prantl 03c6d31a3b Revert "[IR] Remove the DIExpression field from DIGlobalVariable."
This reverts commit 289902 while investigating bot berakage.

llvm-svn: 289906
2016-12-16 01:00:30 +00:00
Adrian Prantl ce13935776 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

llvm-svn: 289902
2016-12-16 00:36:43 +00:00
Teresa Johnson 185b4ab6d4 [ThinLTO] Stop importing constant global vars as copies in the backend
Summary:
We were doing an optimization in the ThinLTO backends of importing
constant unnamed_addr globals unconditionally as a local copy (regardless
of whether the thin link decided to import them). This should be done in
the thin link instead, so that resulting exported references are marked
and promoted appropriately, but will need a summary enhancement to mark
these variables as constant unnamed_addr.

The function import logic during the thin link was trying to handle
this proactively, by conservatively marking all values referenced in
the initializer lists of exported global variables as also exported.
However, this only handled values referenced directly from the
initializer list of an exported global variable. If the value is itself
a constant unnamed_addr variable, we could end up exporting its
references as well. This caused multiple issues. The first is that the
transitively exported references weren't promoted. Secondly, some could
not be promoted/renamed (e.g. they had a section or other constraint).
recursively, instead of just adding the first level of initializer list
references to the ExportList directly.

Remove this optimization and the associated handling in the function
import backend. SPEC measurements indicate we weren't getting much
from it in any case.

Fixes PR31052.

Reviewers: mehdi_amini

Subscribers: krasin, llvm-commits

Differential Revision: https://reviews.llvm.org/D26880

llvm-svn: 288446
2016-12-02 01:02:30 +00:00
Peter Collingbourne 3cb86272fc Linker: Remove unnecessary call to copyMetadata in IRLinker::linkGlobalVariable.
This was causing us to create duplicate metadata on global variables.
Debug info test case by Adrian Prantl, additional test cases by me.

Fixes PR31012.

Differential Revision: https://reviews.llvm.org/D26622

llvm-svn: 286905
2016-11-14 23:18:38 +00:00
Mehdi Amini b53b62eb69 Fix autoupgrade logic for Objective-C class properties module flag
Previous we were issuing an error when linking a module containing
the new Objective-C metadata structure for class properties with an
"old" one.
Now instead we downgrade the module flag so that the Objective-C
runtime does not expect the new metadata structure.

This is consistent with what ld64 is doing on binary files.

Differential Revision: https://reviews.llvm.org/D24620

llvm-svn: 281685
2016-09-16 00:38:18 +00:00
Peter Collingbourne d4135bbc30 DebugInfo: New metadata representation for global variables.
This patch reverses the edge from DIGlobalVariable to GlobalVariable.
This will allow us to more easily preserve debug info metadata when
manipulating global variables.

Fixes PR30362. A program for upgrading test cases is attached to that
bug.

Differential Revision: http://reviews.llvm.org/D20147

llvm-svn: 281284
2016-09-13 01:12:59 +00:00
Duncan P. N. Exon Smith 9cbc69d1fe IR: Drop uniquing when an MDNode Value operand is deleted
This is a fix for PR28697.

An MDNode can indirectly refer to a GlobalValue, through a
ConstantAsMetadata.  When the GlobalValue is deleted, the MDNode operand
is reset to `nullptr`.  If the node is uniqued, this can lead to a
hard-to-detect cache invalidation in a Metadata map that's shared across
an LLVMContext.

Consider:

 1. A map from Metadata* to `T` called RemappedMDs.
 2. A node that references a global variable, `!{i1* @GV}`.
 3. Insert `!{i1* @GV} -> SomeT` in the map.
 4. Delete `@GV`, leaving behind `!{null} -> SomeT`.

Looking up the generic and uninteresting `!{null}` gives you `SomeT`,
which is likely related to `@GV`.  Worse, `SomeT`'s lifetime may be tied
to the deleted `@GV`.

This occurs in practice in the shared ValueMap used since r266579 in the
IRMover.  Other code that handles more than one Module (with different
lifetimes) in the same LLVMContext could hit it too.

The fix here is a partial revert of r225223: in the rare case that an
MDNode operand is a ConstantAsMetadata (i.e., wrapping a node from the
Value hierarchy), drop uniquing if it gets replaced with `nullptr`.
This changes step #4 above to leave behind `distinct !{null} -> SomeT`,
which can't be confused with the generic `!{null}`.

In theory, this can cause some churn in the LLVMContext's MDNode
uniquing map when Values are being deleted.  However:

  - The number of GlobalValues referenced from uniqued MDNodes is
    expected to be quite small.  E.g., the debug info metadata schema
    only references GlobalValues from distinct nodes.

  - Other Constants have the lifetime of the LLVMContext, whose teardown
    is careful to drop references before deleting the constants.

As a result, I don't expect a compile time regression from this change.

llvm-svn: 277625
2016-08-03 18:19:43 +00:00
Rafael Espindola 2211f015cc Don't verify inputs to the Linker if ODR merging.
This fixes pr28072.

The point, as Duncan pointed out, is that the file is already
partially linked by just reading it.

Long term I think the solution is to make metadata owned by the module
and then the linker will lazily read it and be in charge of all the
linking. Running a verifier in each input will defeat the lazy
loading, but will be legal.

Right now we are at the unfortunate position that to support odr
merging we cannot verify the inputs, which mildly annoying (see test
update).

llvm-svn: 274148
2016-06-29 18:31:48 +00:00
Peter Collingbourne 4f7c16dd53 Linker: Copy metadata when linking declarations.
Differential Revision: http://reviews.llvm.org/D21624

llvm-svn: 273692
2016-06-24 17:42:21 +00:00
Mehdi Amini bcc47419d9 ValueMapper: fix assertion when null-mapping a constant for linking metadata
Summary:
When RF_NullMapMissingGlobalValues is set, mapValue can return null
for GlobalValue. When mapping the operands of a constant that is
referenced from metadata, we need to handle this case and actually
return null instead of mapping this constant.

Reviewers: dexonsmith, rafael

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D20713

llvm-svn: 271129
2016-05-28 17:26:03 +00:00
Peter Collingbourne 1eaa97f439 Linker: teach the IR mover to return llvm::Error.
This will be needed in order to consistently return an Error
to clients of the API being developed in D20268.

Differential Revision: http://reviews.llvm.org/D20550

llvm-svn: 270967
2016-05-27 05:21:35 +00:00
Mehdi Amini 3d4f3a0da9 IRLinker: fix double scheduling of mapping a global value because of an alias
This test was hitting an assertion in the value mapper because
the IRLinker was trying to map two times @A while materializing
the initializer for @C.

Fix http://llvm.org/PR27850

Differential Revision: http://reviews.llvm.org/D20586

llvm-svn: 270757
2016-05-25 21:00:44 +00:00
Rafael Espindola 32483a7641 Make "@name =" mandatory for globals in .ll files.
An oddity of the .ll syntax is that the "@var = " in

@var = global i32 42

is optional. Writing just

global i32 42

is equivalent to

@0 = global i32 42

This means that there is a pretty big First set at the top level. The
current implementation maintains it manually. I was trying to refactor
it, but then started wondering why keep it a all. I personally find the
above syntax confusing. It looks like something is missing.

This patch removes the feature and simplifies the parser.

llvm-svn: 269096
2016-05-10 18:22:45 +00:00
Duncan P. N. Exon Smith a59d3e5af8 DebugInfo: Remove MDString-based type references
Eliminate DITypeIdentifierMap and make DITypeRef a thin wrapper around
DIType*.  It is no longer legal to refer to a DICompositeType by its
'identifier:', and DIBuilder no longer retains all types with an
'identifier:' automatically.

Aside from the bitcode upgrade, this is mainly removing logic to resolve
an MDString-based reference to an actualy DIType.  The commits leading
up to this have made the implicit type map in DICompileUnit's
'retainedTypes:' field superfluous.

This does not remove DITypeRef, DIScopeRef, DINodeRef, and
DITypeRefArray, or stop using them in DI-related metadata.  Although as
of this commit they aren't serving a useful purpose, there are patchces
under review to reuse them for CodeView support.

The tests in LLVM were updated with deref-typerefs.sh, which is attached
to the thread "[RFC] Lazy-loading of debug info metadata":

  http://lists.llvm.org/pipermail/llvm-dev/2016-April/098318.html

llvm-svn: 267296
2016-04-23 21:08:00 +00:00
Rafael Espindola 15ca14c0b9 Fix recursive -only-needed.
We were assuming that only linkonce_odr GVs were lazy linked.

llvm-svn: 266995
2016-04-21 14:56:33 +00:00
Mehdi Amini bda3c97c16 ThinLTO/ModuleLinker: add a flag to not always pull-in linkonce when performing importing
Summary:
The function importer already decided what symbols need to be pulled
in. Also these magically added ones will not be in the export list
for the source module, which can confuse the internalizer for
instance.

Reviewers: tejohnson, rafael

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D19096

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266948
2016-04-21 01:59:39 +00:00
Mehdi Amini bb3a1d92f3 ThinLTO: never promote as external weak
This linkage is *not* intended to express that a declaration refers
to a weak symbol, but that the symbol might not be present at link
time. I don't believe it was the intent.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266856
2016-04-20 04:18:11 +00:00
Duncan P. N. Exon Smith 9738602869 IR: Enable debug info type ODR uniquing for forward decls
Add a new method, DICompositeType::buildODRType, that will create or
mutate the DICompositeType for a given ODR identifier, and use it in
LLParser and BitcodeReader instead of DICompositeType::getODRType.

The logic is as follows:

  - If there's no node, create one with the given arguments.
  - Else, if the current node is a forward declaration and the new
    arguments would create a definition, mutate the node to match the
    new arguments.
  - Else, return the old node.

This adds a missing feature supported by the current DITypeIdentifierMap
(which I'm slowly making redudant).  The only remaining difference is
that the DITypeIdentifierMap has a "the-last-one-wins" rule, whereas
DICompositeType::buildODRType has a "the-first-one-wins" rule.

For now I'm leaving behind DICompositeType::getODRType since it has
obvious, low-level semantics that are convenient for unit testing.

llvm-svn: 266786
2016-04-19 18:00:19 +00:00
Duncan P. N. Exon Smith b84b4164ec Linker: Simplify test/Linker/dicompositetype-unique.ll, NFC
Simplify the test logic a little, sharing logic between the two linking
directions by specifying -check-prefix multiple times.  Now it's more
obvious what's hte same and different between the two directions, and
there is less CHECK duplication.  This is a prep for expanding the test.

llvm-svn: 266773
2016-04-19 17:43:43 +00:00
Mehdi Amini 113adde594 ModuleLinker: Do not import linkonce/weak as "external_weak"
Summary:
There is no reason to have a weak reference because the external
definition will be weak.

Reviewers: rafael

Subscribers: llvm-commits, tejohnson

Differential Revision: http://reviews.llvm.org/D19267

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266750
2016-04-19 16:11:05 +00:00
Duncan P. N. Exon Smith 0b0271ef97 IR: getOrInsertODRUniquedType => DICompositeType::getODRType, NFC
Lift the API for debug info ODR type uniquing up a layer.  Instead of
clients managing the map directly on the LLVMContext, add a static
method to DICompositeType called getODRType and handle the map in the
background.  Also adds DICompositeType::getODRTypeIfExists, so far just
for convenience in the unit tests.

This simplifies the logic in LLParser and BitcodeReader.  Because of
argument spam there are actually a few more lines of code now; I'll see
if I come up with a reasonable way to clean that up.

llvm-svn: 266742
2016-04-19 14:55:09 +00:00
Paul Robinson 43d1e45347 [DWARF] Force a linkage_name on an inlined subprogram's abstract origin.
When we suppress linkage names, for a non-inlined subprogram the name
can still be found in the object-file symbol table, because we have
the code address of the subprogram.  This is not necessarily the case
for an inlined subprogram, so we still want to emit the linkage name
in the DWARF.  Put this on the abstract-origin DIE because it's common
to all inlined instances.

Differential Revision: http://reviews.llvm.org/D18706

llvm-svn: 266692
2016-04-18 22:41:41 +00:00
Duncan P. N. Exon Smith 5ab2be094e IR: Use an explicit map for debug info type uniquing
Rather than relying on the structural equivalence of DICompositeType to
merge type definitions, use an explicit map on the LLVMContext that
LLParser and BitcodeReader consult when constructing new nodes.
Each non-forward-declaration DICompositeType with a non-empty
'identifier:' field is stored/loaded from the type map, and the first
definiton will "win".

This map is opt-in: clients that expect ODR types from different modules
to be merged must call LLVMContext::ensureDITypeMap.

  - Clients that just happen to load more than one Module in the same
    LLVMContext won't magically merge types.

  - Clients (like LTO) that want to continue to merge types based on ODR
    identifiers should opt-in immediately.

I have updated LTOCodeGenerator.cpp, the two "linking" spots in
gold-plugin.cpp, and llvm-link (unless -disable-debug-info-type-map) to
set this.

With this in place, it will be straightforward to remove the DITypeRef
concept (i.e., referencing types by their 'identifier:' string rather
than pointing at them directly).

llvm-svn: 266549
2016-04-17 03:58:21 +00:00
Duncan P. N. Exon Smith 05ebfd0938 IR: Use ODR to unique DICompositeType members
Merge members that are describing the same member of the same ODR type,
even if other bits differ.  If the file or line differ, we don't care;
if anything else differs, it's an ODR violation (and we still don't
really care).

For DISubprogram declarations, this looks at the LinkageName and Scope.
For DW_TAG_member instances of DIDerivedType, this looks at the Name and
Scope.  In both cases, we know that the Scope follows ODR rules if it
has a non-empty identifier.

llvm-svn: 266548
2016-04-17 02:30:20 +00:00
Duncan P. N. Exon Smith 4f6f15d2df Linker: Clarify test/Linker/type-unique-odr-a.ll, NFC
Split up the long RUN and clarify the CHECK lines:

  - Explicitly confirm there are no other subprograms inside of "A".

  - Remove checks for "bar" and "baz", which were just implicitly
    checking that there were no other subprograms inside of "A".

This prepares for adding a RUN line which links the two files in the
opposite direction.

llvm-svn: 266543
2016-04-17 00:26:17 +00:00
Adrian Prantl 75819aedf6 [PR27284] Reverse the ownership between DICompileUnit and DISubprogram.
Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICompositeType. DIScopes
point to the DICompileUnit to facilitate type uniquing.

Distinct DISubprograms (with isDefinition: true) are not part of the type
hierarchy and cannot be uniqued. This change removes the subprograms
list from DICompileUnit and instead adds a pointer to the owning compile
unit to distinct DISubprograms. This would make it easy for ThinLTO to
strip unneeded DISubprograms and their transitively referenced debug info.

Motivation
----------

Materializing DISubprograms is currently the most expensive operation when
doing a ThinLTO build of clang.

We want the DISubprogram to be stored in a separate Bitcode block (or the
same block as the function body) so we can avoid having to expensively
deserialize all DISubprograms together with the global metadata. If a
function has been inlined into another subprogram we need to store a
reference the block containing the inlined subprogram.

Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script
that updates LLVM IR testcases to the new format.

http://reviews.llvm.org/D19034
<rdar://problem/25256815>

llvm-svn: 266446
2016-04-15 15:57:41 +00:00
Mehdi Amini 68da426eea Move summary creation out of llvm-as into opt
Summary:
Let keep llvm-as "dumb": it converts textual IR to bitcode. This
commit removes the dependency from llvm-as to libLLVMAnalysis.
We'll add back summary in llvm-as if we get to a textual
representation for it at some point. In the meantime, opt seems
like a better place for that.

Reviewers: tejohnson

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D19032

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266131
2016-04-12 21:35:18 +00:00
Mehdi Amini ae280e54a9 ThinLTO renaming: use module hash instead of position in the summary
This is more robust to changes in the link ordering.

Differential Revision: http://reviews.llvm.org/D18946

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266018
2016-04-11 23:26:46 +00:00
Adrian Prantl ea7eb841a1 Legalize the debug info in this testcase in anticipation of future Verifier improvements.
llvm-svn: 266017
2016-04-11 23:26:31 +00:00
Adrian Prantl 115edcaec1 Add missing DICompileUnit to this testcase
llvm-svn: 265995
2016-04-11 20:58:57 +00:00
Adrian Prantl b01a4d48ac More upgrading of old- and very-old-style debug info in testcases.
llvm-svn: 265953
2016-04-11 15:53:44 +00:00
Adrian Prantl b8089516a5 testcase gardening: update the emissionKind enum to the new syntax. (NFC)
llvm-svn: 265081
2016-04-01 00:16:49 +00:00
Adrian Prantl b939a25707 Move the DebugEmissionKind enum from DIBuilder into DICompileUnit.
This mostly cosmetic patch moves the DebugEmissionKind enum from DIBuilder
into DICompileUnit. DIBuilder is not the right place for this enum to live
in — a metadata consumer should not have to include DIBuilder.h.
I also added a Verifier check that checks that the emission kind of a
DICompileUnit is actually legal.

http://reviews.llvm.org/D18612
<rdar://problem/25427165>

llvm-svn: 265077
2016-03-31 23:56:58 +00:00
Adrian Prantl 4a09777b37 Upgrade some wildly anachronistic debug info in testcases.
llvm-svn: 264797
2016-03-29 22:34:30 +00:00
Rafael Espindola e1c42ac12b Fix another case where we were unconditionally linking linkonce GVs.
With this I think that now llvm-link,  lld and the gold plugin should
agree on which symbol is kept.

llvm-svn: 264292
2016-03-24 15:23:01 +00:00
Rafael Espindola 42e0323768 Fix resolution of linkonce symbols in comdats.
After comdat processing, the symbols still go through regular symbol
resolution.

We were not doing it for linkonce symbols since they are lazy linked.

This fixes pr27044.

llvm-svn: 264288
2016-03-24 14:58:44 +00:00
Rafael Espindola 1ee9fbd842 Fix lazy linking of comdat members.
If not for lazy linking of linkonce GVs, comdats are just a
preprocessing before symbol resolution.

Lazy linking complicates it since when we pick a visible member of
comdat, we have to make sure the rest of it passes symbol resolution
too.

llvm-svn: 264223
2016-03-24 00:06:03 +00:00
Rafael Espindola f2e71244c6 Fix logic for which symbols to keep with comdats.
If a comdat is dropped, all symbols in it are dropped.
If a comdat is kept, the symbols survive to pass regular symbol
resolution.
With this patch we do that for all global symbols.

The added test is a copy of test/tools/gold/X86/comdat.ll that we now
pass.

llvm-svn: 264192
2016-03-23 21:16:33 +00:00
Rafael Espindola 370d528a05 Drop comdats from the dst module if they are not selected.
A really unfortunate design of llvm-link and related libraries is that
they operate one module at a time.

This means they can copy a GV to the destination module that should not
be there in the final result because a later bitcode file takes
precedence.

We already handled cases like a strong GV replacing a weak for example.

One case that is not currently handled is a comdat replacing another.
This doesn't happen in ELF, but with COFF largest selection kind it is
possible.

In "llvm-link a.ll b.ll" if the selected comdat was from a.ll,
everything will work and we will not copy the comdat from b.ll.

But if we run "llvm-link b.ll a.ll", we fail to delete the already
copied comdat from b.ll. This patch fixes that.

llvm-svn: 264103
2016-03-22 21:35:47 +00:00
Mehdi Amini 8d05185a26 Rework linkInModule(), making it oblivious to ThinLTO
Summary:
ThinLTO is relying on linkInModule to import selected function.
However a lot of "magic" was hidden in linkInModule and the IRMover,
who would rename and promote global variables on the fly.

This is moving to an approach where the steps are decoupled and the
client is reponsible to specify the list of globals to import.
As a consequence some test are changed because they were relying on
the previous behavior which was importing the definition of *every*
single global without control on the client side.
Now the burden is on the client to decide if a global has to be imported
or not.

Reviewers: tejohnson

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D18122

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 263863
2016-03-19 00:40:31 +00:00
Teresa Johnson 26ab5772b0 [ThinLTO] Renaming of function index to module summary index (NFC)
(Resubmitting after fixing missing file issue)

With the changes in r263275, there are now more than just functions in
the summary. Completed the renaming of data structures (started in
r263275) to reflect the wider scope. In particular, changed the
FunctionIndex* data structures to ModuleIndex*, and renamed related
variables and comments. Also renamed the files to reflect the changes.

A companion clang patch will immediately succeed this patch to reflect
this renaming.

llvm-svn: 263513
2016-03-15 00:04:37 +00:00
Teresa Johnson cec0cae313 Revert "[ThinLTO] Renaming of function index to module summary index (NFC)"
This reverts commit r263490. Missed a file.

llvm-svn: 263493
2016-03-14 21:18:10 +00:00
Teresa Johnson 892920b358 [ThinLTO] Renaming of function index to module summary index (NFC)
With the changes in r263275, there are now more than just functions in
the summary. Completed the renaming of data structures (started in
r263275) to reflect the wider scope. In particular, changed the
FunctionIndex* data structures to ModuleIndex*, and renamed related
variables and comments. Also renamed the files to reflect the changes.

A companion clang patch will immediately succeed this patch to reflect
this renaming.

llvm-svn: 263490
2016-03-14 21:05:56 +00:00
Teresa Johnson d7e88e515c [ThinLTO] Remove imported available externally defs from comdats.
Summary:
Available externally definitions are considered declarations for the
linker and eventually dropped. As such they are not allowed to be
in comdats. Remove any such imported functions from comdats.

Reviewers: rafael

Subscribers: davidxl, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D16120

llvm-svn: 260122
2016-02-08 18:47:20 +00:00
Rafael Espindola ac60e5f028 Add a test for r258362.
Thanks to Mehdi for finding it.

llvm-svn: 259394
2016-02-01 19:56:12 +00:00
Teresa Johnson 71d12d2a4e [ThinLTO] Find all needed metadata when linking metadata as postpass
For metadata postpass linking, after importing all functions, we need
to recursively walk through any nodes reached via imported functions to
locate needed subprogram metadata. Some might only be reached indirectly
via the variable list for an inlined function.

llvm-svn: 258728
2016-01-25 22:04:56 +00:00
Teresa Johnson f07db00a65 [ThinLTO] Handle DISubprogram reached indirectly from DIImportedEntity
Extend fix for PR26037 to identify DISubprogram reached from a
DIImportedEntity via a DILexicalBlock.

llvm-svn: 258722
2016-01-25 21:29:55 +00:00
Teresa Johnson e0373a6796 Revert obsolete llvm-link -preserve-modules option/test
This testing mode is now obsolete with the change to linkInModule
to take a std::unique_ptr to Module.

llvm-svn: 258399
2016-01-21 14:28:52 +00:00
Evgeniy Stepanov 9fb70f53ce Fix PR26152.
Fix the condition for when the new global takes over the name of
the existing one to be the negation of the condition for the new
global to get internal linkage.

llvm-svn: 258355
2016-01-20 22:05:50 +00:00
Keno Fischer 81e2e9ef86 Reapply r257105 "[Verifier] Check that debug values have proper size"
I originally reapplied this in 257550, but had to revert again due to bot
breakage. The only change in this version is to allow either the TypeSize
or the TypeAllocSize of the variable to be the one represented in debug info
(hopefully in the future we can figure out how to encode the difference).
Additionally, several bot failures following r257550, were due to
optimizer bugs now fixed in r257787 and r257795.

r257550 commit message was:

```
The follow extra changes were made to test cases:

Manually making the variable be the actual type instead of a pointer
to avoid pointer-size differences in generic code:

    LLVM :: DebugInfo/Generic/2010-03-24-MemberFn.ll
    LLVM :: DebugInfo/Generic/2010-04-06-NestedFnDbgInfo.ll
    LLVM :: DebugInfo/Generic/2010-05-03-DisableFramePtr.ll
    LLVM :: DebugInfo/Generic/varargs.ll

Delete sizing information from debug info for the same reason
(but the presence of the pointer was important to the test case):

    LLVM :: DebugInfo/Generic/restrict.ll
    LLVM :: DebugInfo/Generic/tu-composite.ll
    LLVM :: Linker/type-unique-type-array-a.ll
    LLVM :: Linker/type-unique-simple2.ll

Fixing an incorrect DW_OP_deref

    LLVM :: DebugInfo/Generic/2010-05-03-OriginDIE.ll

Fixing a missing DW_OP_deref

    LLVM :: DebugInfo/Generic/incorrect-variable-debugloc.ll

Additionally, clang should no longer complain during bootstrap should no
longer happen after r257534.

The original commit message was:
``
Summary:
Teach the Verifier to make sure that the storage size given to llvm.dbg.declare
or the value size given to llvm.dbg.value agree with what is declared in
DebugInfo. This is implicitly assumed in a number of passes (e.g. in SROA).
Additionally this catches a number of common mistakes, such as passing a
pointer when a value was intended or vice versa.

One complication comes from stack coloring which modifies the original IR when
it merges allocas in order to make sure that if AA falls back to the IR it gets
the correct result. However, given this new invariant, indiscriminately
replacing one alloca by a different (differently sized one) is no longer valid.
Fix this by just undefing out any use of the alloca in a dbg.declare in this
case.

Additionally, I had to fix a number of test cases. Of particular note:
- I regenerated dbg-changes-codegen-branch-folding.ll from the given source as
  it was affected by the bug fixed in r256077
- two-cus-from-same-file.ll was changed to avoid having a variable-typed debug
  variable as that would depend on the target, even though this test is
  supposed to be generic
- I had to manually declared size/align for reference type. See also the
  discussion for D14275/r253186.
- fpstack-debuginstr-kill.ll required changing `double` to `long double`
- most others were just a question of adding OP_deref
``

```

llvm-svn: 257850
2016-01-15 00:46:17 +00:00
Keno Fischer 78e5c9e6e2 Re-Revert r257105 (Verifier debug info changes)
While I investigate some new buildbot failures. This was originally reapplied
as r257550 and r257558.

llvm-svn: 257563
2016-01-13 02:31:14 +00:00
Keno Fischer 25916079ff Reapply r257105 "[Verifier] Check that debug values have proper size"
The follow extra changes were made to test cases:

Manually making the variable be the actual type instead of a pointer
to avoid pointer-size differences in generic code:

    LLVM :: DebugInfo/Generic/2010-03-24-MemberFn.ll
    LLVM :: DebugInfo/Generic/2010-04-06-NestedFnDbgInfo.ll
    LLVM :: DebugInfo/Generic/2010-05-03-DisableFramePtr.ll
    LLVM :: DebugInfo/Generic/varargs.ll

Delete sizing information from debug info for the same reason
(but the presence of the pointer was important to the test case):

    LLVM :: DebugInfo/Generic/restrict.ll
    LLVM :: DebugInfo/Generic/tu-composite.ll
    LLVM :: Linker/type-unique-type-array-a.ll
    LLVM :: Linker/type-unique-simple2.ll

Fixing an incorrect DW_OP_deref

    LLVM :: DebugInfo/Generic/2010-05-03-OriginDIE.ll

Fixing a missing DW_OP_deref

    LLVM :: DebugInfo/Generic/incorrect-variable-debugloc.ll

Additionally, clang should no longer complain during bootstrap should no
longer happen after r257534.

The original commit message was:
```
Summary:
Teach the Verifier to make sure that the storage size given to llvm.dbg.declare
or the value size given to llvm.dbg.value agree with what is declared in
DebugInfo. This is implicitly assumed in a number of passes (e.g. in SROA).
Additionally this catches a number of common mistakes, such as passing a
pointer when a value was intended or vice versa.

One complication comes from stack coloring which modifies the original IR when
it merges allocas in order to make sure that if AA falls back to the IR it gets
the correct result. However, given this new invariant, indiscriminately
replacing one alloca by a different (differently sized one) is no longer valid.
Fix this by just undefing out any use of the alloca in a dbg.declare in this
case.

Additionally, I had to fix a number of test cases. Of particular note:
- I regenerated dbg-changes-codegen-branch-folding.ll from the given source as
  it was affected by the bug fixed in r256077
- two-cus-from-same-file.ll was changed to avoid having a variable-typed debug
  variable as that would depend on the target, even though this test is
  supposed to be generic
- I had to manually declared size/align for reference type. See also the
  discussion for D14275/r253186.
- fpstack-debuginstr-kill.ll required changing `double` to `long double`
- most others were just a question of adding OP_deref
```

llvm-svn: 257550
2016-01-13 00:31:44 +00:00
Ahmed Bougacha a7324a2823 [Linker] Also treat a DIImportedEntity scope DISubprogram as needed.
Follow-up to r257000: DIImportedEntity can reach a DISubprogram via
its entity, but also via its scope. Handle the latter case as well.

PR26037.

llvm-svn: 257019
2016-01-07 03:14:59 +00:00
Teresa Johnson b951558294 Always treat DISubprogram reached by DIImportedEntity as needed.
It is illegal to have a null entity in a DIImportedEntity, so
we must link in a DISubprogram metadata node referenced by one,
even if the associated function is not linked in or inlined anywhere.

Fixes PR26037.

llvm-svn: 257000
2016-01-07 00:06:27 +00:00
Teresa Johnson 0e7c82cb69 [ThinLTO/LTO] Don't link in unneeded metadata
Summary:
Third patch split out from http://reviews.llvm.org/D14752.

Only map in needed DISubroutine metadata (imported or otherwise linked
in functions and other DISubroutine referenced by inlined instructions).
This is supported for ThinLTO, LTO and llvm-link --only-needed, with
associated tests for each one.

Depends on D14838.

Reviewers: dexonsmith, joker.eph

Subscribers: davidxl, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D14843

llvm-svn: 256003
2015-12-18 17:51:37 +00:00
Teresa Johnson e5a6191732 [ThinLTO] Metadata linking for imported functions
Summary:
Second patch split out from http://reviews.llvm.org/D14752.

Maps metadata as a post-pass from each module when importing complete,
suturing up final metadata to the temporary metadata left on the
imported instructions.

This entails saving the mapping from bitcode value id to temporary
metadata in the importing pass, and from bitcode value id to final
metadata during the metadata linking postpass.

Depends on D14825.

Reviewers: dexonsmith, joker.eph

Subscribers: davidxl, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D14838

llvm-svn: 255909
2015-12-17 17:14:09 +00:00
Rafael Espindola 9d2bfc4874 Use diagnostic handler in the LLVMContext
This patch converts code that has access to a LLVMContext to not take a
diagnostic handler.

This has a few advantages

* It is easier to use a consistent diagnostic handler in a single program.
* Less clutter since we are not passing a handler around.

It does make it a bit awkward to implement some C APIs that return a
diagnostic string. I will propose new versions of these APIs and
deprecate the current ones.

llvm-svn: 255571
2015-12-14 23:17:03 +00:00
Rafael Espindola a8547d35e9 Fix another case where the linkage was not set.
llvm-svn: 255272
2015-12-10 18:44:26 +00:00
Rafael Espindola caabe22832 Slit lib/Linker in two.
A linker normally has two stages: symbol resolution and "moving stuff".

In lib/Linker there is the complication of lazy linking some globals,
but it was still far more mixed than it needed to.

This splits the linker into a lower level IRMover and the linker proper.
The IRMover just takes a list of globals to move and a callback that
lets the user control what is lazy linked.

The main motivation is that now tools/gold (and soon lld) can use their
own symbol resolution to instruct IRMover what to do.

llvm-svn: 255254
2015-12-10 14:19:35 +00:00
Rafael Espindola ed11bd286f Synchronize the logic for deciding to link a gv.
We were deciding to not link an available_externally gv over a
declaration, but then copying over the body anyway.

llvm-svn: 255169
2015-12-09 22:44:00 +00:00
Rafael Espindola 758f7794bb Add a test showing that we internalize lazily linked GVs.
llvm-svn: 254989
2015-12-08 02:38:14 +00:00
Rafael Espindola a98a3be2c4 Simplify test. NFC.
llvm-svn: 254987
2015-12-08 02:29:45 +00:00
Rafael Espindola bd03c50336 Link declaration lazily.
We already linked available_externally and linkonce lazily, this just
adds declarations to the list.

llvm-svn: 254917
2015-12-07 16:31:41 +00:00
Rafael Espindola 3c9d3f75b7 Simplify test.
llvm-svn: 254916
2015-12-07 16:01:40 +00:00
Rafael Espindola a1240d8cb3 Change how the linker handles the old llvm.global_ctors.
Now instead of changing it to the new format and then linking, it just
handles the old format while copying it over.

The main differences are:

* There is no rauw in the source module.
* An old format input is always upgraded.

The first item helps with having a sane API that passes in a GV list to
the linker.

The second one is a small step in deprecating the old format.

llvm-svn: 254907
2015-12-07 13:24:23 +00:00
Rafael Espindola c0ccdc388c Simplify test. NFC.
llvm-svn: 254631
2015-12-03 19:10:55 +00:00
Teresa Johnson 1e20a652ee [ThinLTO] Appending linkage fixes
Summary:
Fix import from module with appending var, which cannot be imported. The
first fix is to remove an overly-aggressive error check.

The second fix is to deal with restructuring introduced to the module
linker yesterday in r254418 (actually, this fix was included already
in r254559, just added some additional cleanup).

Test by Mehdi Amini.

Reviewers: joker.eph, rafael

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D15156

llvm-svn: 254624
2015-12-03 18:20:05 +00:00
Rafael Espindola 4b5ec26373 Switch the linker to having a whitelist of GVs.
This replaces DoNotLinkFromSource with ValuesToLink. It also moves the
computation of ValuesToLink earlier.

It is a bit simpler and an important step in slitting the linker into an
ir mover and a linker proper.

The test change is because we now avoid creating dead declarations.

llvm-svn: 254559
2015-12-02 22:59:04 +00:00
Rafael Espindola 8c04472edf Delete what is now duplicated code.
Having to import an alias as declaration is not thinlto specific.

The test difference are because when we already have a decl and we are
not importing it, we just leave the decl alone.

llvm-svn: 254556
2015-12-02 22:22:24 +00:00
Rafael Espindola 0a80da0bec Also copy private linkage globals when needed.
This was an omission when handling COFF style comdats with local keys.
Should fix the sanitizer-windows bot.

llvm-svn: 254543
2015-12-02 20:57:33 +00:00
Rafael Espindola 769efe621a Don't copy information from aliasee to alias.
They are independent.

llvm-svn: 254541
2015-12-02 20:03:17 +00:00
Rafael Espindola f3518c955b Fix linking when we copy over only a decl.
We were failing to copy the fact that the GV is weak and in the case of
an alias, producing invalid IR.

llvm-svn: 254538
2015-12-02 19:30:52 +00:00
Rafael Espindola 9b04181d81 Add an interesting case we already get right.
llvm-svn: 254514
2015-12-02 15:02:43 +00:00
Rafael Espindola b318fcbd8b Simplify test. NFC.
llvm-svn: 254419
2015-12-01 15:46:46 +00:00
Rafael Espindola baa3bf8f76 Bring r254336 back:
The difference is that now we don't error on out-of-comdat access to
internal global values. We copy them instead. This seems to match the
expectation of COFF linkers (see pr25686).

Original message:

    Start deciding earlier what to link.

    A traditional linker is roughly split in symbol resolution and
"copying
    stuff".

    The two tasks are badly mixed in lib/Linker.

    This starts splitting them apart.

    With this patch there are no direct call to linkGlobalValueBody or
    linkGlobalValueProto. Everything is linked via WapValue.

    This also includes a few fixes:
    * A GV goes undefined if the comdat is dropped (comdat11.ll).
    * We error if an internal GV goes undefined (comdat13.ll).
    * We don't link an unused comdat.

    The first two match the behavior of an ELF linker. The second one is
    equivalent to running globaldce on the input.

llvm-svn: 254418
2015-12-01 15:19:48 +00:00
Rafael Espindola e9841a6bb5 This reverts commit r254336 and r254344.
They broke a bot and I am debugging why.

llvm-svn: 254347
2015-11-30 23:54:19 +00:00
Rafael Espindola a891957002 Disable a consistency check.
Trying to figure out why it fails on a bot but passes locally.

llvm-svn: 254344
2015-11-30 23:05:25 +00:00
Rafael Espindola c109200c53 Start deciding earlier what to link.
A traditional linker is roughly split in symbol resolution and "copying
stuff".

The two tasks are badly mixed in lib/Linker.

This starts splitting them apart.

With this patch there are no direct call to linkGlobalValueBody or
linkGlobalValueProto. Everything is linked via WapValue.

This also includes a few fixes:
* A GV goes undefined if the comdat is dropped (comdat11.ll).
* We error if an internal GV goes undefined (comdat13.ll).
* We don't link an unused comdat.

The first two match the behavior of an ELF linker. The second one is
equivalent to running globaldce on the input.

llvm-svn: 254336
2015-11-30 22:01:43 +00:00
Reid Kleckner 8a71273d89 Avoid writing to source directory of tests
llvm-svn: 254324
2015-11-30 20:36:23 +00:00
Rafael Espindola c98b20b0d6 Fix another llvm.ctors merging bug.
We were not looking past casts to see if an element should be included
or not.

llvm-svn: 254313
2015-11-30 18:54:24 +00:00
Rafael Espindola 290409ef5d Make this test less strict.
We just want to test what is copied, no the order.

llvm-svn: 254255
2015-11-29 14:53:06 +00:00
Rafael Espindola c945c8d22e Correctly handle llvm.global_ctors merging.
We were not handling the case where an entry must be dropped and the
destination module has no llvm.global_ctors.

llvm-svn: 254241
2015-11-29 03:29:42 +00:00
Rafael Espindola 9f30fac4d8 Fix a crash when writing merged bitcode.
Playing with mutateType in here was making getValueType and getType
incompatible.

llvm-svn: 254240
2015-11-29 03:21:30 +00:00
Rafael Espindola 5aafbac081 Pass .ll directly to llvm-link.
llvm-svn: 254214
2015-11-27 23:47:15 +00:00
Rafael Espindola 57e61231ad Pass .ll directly to llvm-link
llvm-svn: 254213
2015-11-27 23:21:45 +00:00
Rafael Espindola 138f895655 Modernize the test a bit
Remove out of date comment.
Pass .ll files to llvm-link.

llvm-svn: 254210
2015-11-27 23:13:17 +00:00
Rafael Espindola 8934577171 Disallow aliases to available_externally.
They are as much trouble as aliases to declarations. They are requiring
the code generator to define a symbol with the same value as another
symbol, but the second symbol is undefined.

If representing this is important for some optimization, we could add
support for available_externally aliases. They would be *required* to
point to a declaration (or available_externally definition).

llvm-svn: 254170
2015-11-26 19:22:59 +00:00
Rafael Espindola d1beb07d39 Have a single way for creating unique value names.
We had two code paths. One would create names like "foo.1" and the other
names like "foo1".

For globals it is important to use "foo.1" to help C++ name demangling.
For locals there is no strong reason to go one way or the other so I
kept the most common mangling (foo1).

llvm-svn: 253804
2015-11-22 00:16:24 +00:00
Teresa Johnson 6290dbc0f7 [ThinLTO] Handle bitcode without function summary sections gracefully
Summary:
Several fixes to the handling of bitcode files without function summary
sections so that they are skipped during ThinLTO processing in llvm-lto
and the gold plugin when appropriate instead of aborting.

1 Don't assert when trying to add a FunctionInfo that doesn't have
  a summary attached.
2 Skip FunctionInfo structures that don't have attached function summary
  sections when trying to create the combined function summary.
3 In both llvm-lto and gold-plugin, check whether a bitcode file has
  a function summary section before trying to parse the index, and skip
  the bitcode file if it does not.
4 Fix hasFunctionSummaryInMemBuffer in BitcodeReader, which had a bug
  where we returned to early while looking for the summary section.

Also added llvm-lto and gold-plugin based tests for cases where we
don't have function summaries in the bitcode file. I verified that
either the first couple fixes described above are enough to avoid the
crashes, or fixes 1,3,4. But have combined them all here for added
robustness.

Reviewers: joker.eph

Subscribers: llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D14903

llvm-svn: 253796
2015-11-21 21:55:48 +00:00
Teresa Johnson 5bc88be11e llvm-link option and test for recent metadata mapping bug
Summary:
Add a -preserve-modules option to llvm-link that simulates LTO
clients that don't destroy modules as they are linked. This enables
reproduction of a recent bug introduced by a metadata linking change
that was only caught when the modules weren't destroyed before
writing bitcode (LTO on Windows).

See http://llvm.org/viewvc/llvm-project?view=revision&revision=253170
for more details on the original bug and the fix.

Confirmed the new test added here reproduces the failure using the new
option when I suppress the fix.

Reviewers: pcc

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14818

llvm-svn: 253740
2015-11-21 00:35:38 +00:00
Pete Cooper 67cf9a723b Revert "Change memcpy/memset/memmove to have dest and source alignments."
This reverts commit r253511.

This likely broke the bots in
http://lab.llvm.org:8011/builders/clang-ppc64-elf-linux2/builds/20202
http://bb.pgr.jp/builders/clang-3stage-i686-linux/builds/3787

llvm-svn: 253543
2015-11-19 05:56:52 +00:00
Pete Cooper 72bc23ef02 Change memcpy/memset/memmove to have dest and source alignments.
Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

These intrinsics currently have an explicit alignment argument which is
required to be a constant integer.  It represents the alignment of the
source and dest, and so must be the minimum of those.

This change allows source and dest to each have their own alignments
by using the alignment attribute on their arguments.  The alignment
argument itself is removed.

There are a few places in the code for which the code needs to be
checked by an expert as to whether using only src/dest alignment is
safe.  For those places, they currently take the minimum of src/dest
alignments which matches the current behaviour.

For example, code which used to read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false)
will now read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 8 %dest, i8* align 8 %src, i32 500, i1 false)

For out of tree owners, I was able to strip alignment from calls using sed by replacing:
  (call.*llvm\.memset.*)i32\ [0-9]*\,\ i1 false\)
with:
  $1i1 false)

and similarly for memmove and memcpy.

I then added back in alignment to test cases which needed it.

A similar commit will be made to clang which actually has many differences in alignment as now
IRBuilder can generate different source/dest alignments on calls.

In IRBuilder itself, a new argument was added.  Instead of calling:
  CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, /* isVolatile */ false)
you now call
  CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, SrcAlign, /* isVolatile */ false)

There is a temporary class (IntegerAlignment) which takes the source alignment and rejects
implicit conversion from bool.  This is to prevent isVolatile here from passing its default
parameter to the source alignment.

Note, changes in future can now be made to codegen.  I didn't change anything here, but this
change should enable better memcpy code sequences.

Reviewed by Hal Finkel.

llvm-svn: 253511
2015-11-18 22:17:24 +00:00
Teresa Johnson ba5d68dfff [ThinLTO] Update test to be more tolerant of ordering changes
Update the ThinLTO function importing test to use DAG forms of checks so
that it is more tolerant of changes to relative ordering between
imported decls/defs. This reduces the number of changes required by the
comdat importing patch I am sending for review shortly.

llvm-svn: 252932
2015-11-12 19:31:46 +00:00
Teresa Johnson 2d5fb8cac4 Ensure ModuleLinker materializes complete comdat groups
Summary:
The module linker lazy links some "discardable if unused" global
values (e.g. linkonce), materializing and linking them only
if they are referenced in the module. If a comdat group contains a
linkonce member that is not referenced, however, it would not be
materialized and linked, leading to an incomplete comdat group.

If there are other object files not part of the same LTO link that also
define and use that comdat group, the linker may select the incomplete
group leading to link time unsats.

To solve this, whenever a global value body is linked, make sure we
materialize any other members of the same comdat group that are not yet
materialized. This ensures they are in the lazy link list and get linked
as well.

Added new test and adjusted old test to remove parts that didn't
make sense with fix.

Reviewers: rafael

Subscribers: dexonsmith, davidxl, llvm-commits

Differential Revision: http://reviews.llvm.org/D14516

llvm-svn: 252647
2015-11-10 21:09:06 +00:00
Teresa Johnson 3cd8161c9b [ThinLTO] WeakAny fixes/cleanup
Ensure WeakAny variables are imported as ExternalWeak declarations. To
handle WeakAny more consistently and fix this issue:

1) Update helper doImportAsDefinition to properly flag WeakAny variables
   and aliases as not importing defintions.

   Update callers of doImportAsDefinition to remove now redundant checks for
   WeakAny aliases, or ignore aliases, as appropriate.

2) Add any !doImportAsDefinition GVs to DoNotLinkFromSource set during
   linking of the GV prototype, where we usually add GVs to the
   DoNotLinkFromSource set for other reasons.

   Remove now unnecessary adding of WeakAny aliases to
   DoNotLinkFromSource set from copyGlobalAliasProto.

   Remove now unnecessary guard against linking non-imported function
   bodies from ModuleLinker::run.

llvm-svn: 252626
2015-11-10 18:20:11 +00:00
Teresa Johnson 1063293a89 Restore "Move metadata linking after lazy global materialization/linking."
Summary:
This reverts commit r251965.

Restore "Move metadata linking after lazy global materialization/linking."

This restores commit r251926, with fixes for the LTO bootstrapping bot
failure.

The bot failure was caused by references from debug metadata to
otherwise unreferenced globals. Previously, this caused the lazy linking
to link in their defs, which is unnecessary. With this patch, because
lazy linking is complete when we encounter the metadata reference, the
materializer created a declaration. For definitions such as aliases and
comdats, it is illegal to have a declaration. Furthermore, metadata
linking should not change code generation. Therefore, when linking of
global value bodies is complete, the materializer will simply return
nullptr as the new reference for the linked metadata.

This change required fixing a different test to ensure there was a
real reference to a linkonce global that was only being reference from
metadata.

Note that the new changes to the only-needed-named-metadata.ll test
illustrate an issue with llvm-link -only-needed handling of comdat
groups, whereby it may result in an incomplete comdat group. I note this
in the test comments, but the issue is orthogonal to this patch (it can
be reproduced without any metadata at head).

Reviewers: dexonsmith, rafael, tra

Subscribers: tobiasvk, joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D14447

llvm-svn: 252320
2015-11-06 17:50:53 +00:00
Teresa Johnson 189b252652 Restore "Move metadata linking after lazy global materialization/linking."
This reverts commit r251965.

llvm-svn: 252319
2015-11-06 17:50:48 +00:00
Peter Collingbourne d4bff30370 DI: Reverse direction of subprogram -> function edge.
Previously, subprograms contained a metadata reference to the function they
described. Because most clients need to get or set a subprogram for a given
function rather than the other way around, this created unneeded inefficiency.

For example, many passes needed to call the function llvm::makeSubprogramMap()
to build a mapping from functions to subprograms, and the IR linker needed to
fix up function references in a way that caused quadratic complexity in the IR
linking phase of LTO.

This change reverses the direction of the edge by storing the subprogram as
function-level metadata and removing DISubprogram's function field.

Since this is an IR change, a bitcode upgrade has been provided.

Fixes PR23367. An upgrade script for textual IR for out-of-tree clients is
attached to the PR.

Differential Revision: http://reviews.llvm.org/D14265

llvm-svn: 252219
2015-11-05 22:03:56 +00:00
Teresa Johnson f1b0a6e37c [ThinLTO] Always set linkage type to external when converting alias
When converting an alias to a non-alias when the aliasee is not
imported, ensure that the linkage type is set to external so that it is
a valid linkage type. Added a test case that exposed this issue.

llvm-svn: 252054
2015-11-04 16:01:16 +00:00
Teresa Johnson 255787a969 Revert "Move metadata linking after lazy global materialization/linking."
This reverts commit r251926. I believe this is causing an LTO
bootstrapping bot failure
(http://lab.llvm.org:8080/green/job/llvm-stage2-cmake-RgLTO_build/3669/).

Haven't been able to repro it yet, but after looking at the metadata I
am pretty sure I know what is going on.

llvm-svn: 251965
2015-11-03 19:36:04 +00:00
Teresa Johnson 07b825b01c Move metadata linking after lazy global materialization/linking.
Summary:
Currently, named metadata is linked before the LazilyLinkGlobalValues
list is walked and materialized/linked. As a result, references
from DISubprogram and DIGlobalVariable metadata to yet unmaterialized
functions and variables cause them to be added to the lazy linking
list and their definitions are materialized and linked.

This makes the llvm-link -only-needed option not have the intended
effect when debug information is present, as the otherwise unneeded
functions/variables are still linked in.

Additionally, for ThinLTO I have implemented a mechanism to only link
in debug metadata needed by imported functions. Moving named metadata
linking after lazy GV linking will facilitate applying this mechanism
to the LTO and "llvm-link -only-needed" cases as well.

Reviewers: dexonsmith, tra, dblaikie

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14195

llvm-svn: 251926
2015-11-03 15:11:27 +00:00
Teresa Johnson c7ed52f2ba Restore "Support for ThinLTO function importing and symbol linking."
This restores commit r251837, with the new library dependence added to
llvm-link/Makefile to address bot failures.

llvm-svn: 251866
2015-11-03 00:14:15 +00:00
Teresa Johnson 227a923140 Revert "Support for ThinLTO function importing and symbol linking."
This reverts commit r251837, due to a number of bot failures of the form:

/home/grosser/buildslave/perf-x86_64-penryn-O3-polly-fast/llvm.obj/tools/llvm-link/Release+Asserts/llvm-link.o:llvm-link.cpp:function
loadIndex(llvm::LLVMContext&, llvm::Module const*): error: undefined
reference to
'llvm::object::FunctionIndexObjectFile::create(llvm::MemoryBufferRef,
llvm::LLVMContext&, llvm::Module const*, bool)'
/home/grosser/buildslave/perf-x86_64-penryn-O3-polly-fast/llvm.obj/tools/llvm-link/Release+Asserts/llvm-link.o:llvm-link.cpp:function
loadIndex(llvm::LLVMContext&, llvm::Module const*): error: undefined
reference to 'llvm::object::FunctionIndexObjectFile::takeIndex()'

I'm not sure why these are happening - I added Object to the requred
libraries in tools/llvm-link/LLVMBuild.txt and the LLVM_LINK_COMPONENTS
in tools/llvm-link/CMakeLists.txt. Confirmed for my build that these
symbols come out of libLLVMObject.a. What am I missing?

llvm-svn: 251841
2015-11-02 22:17:32 +00:00
Teresa Johnson b1d4a39990 Support for ThinLTO function importing and symbol linking.
Summary:
Support for necessary linkage changes and symbol renaming during
ThinLTO function importing.

Also includes llvm-link support for manually importing functions
and associated llvm-link based tests.

Note that this does not include support for intelligently importing
metadata, which is currently imported duplicate times. That support will
be in the follow-on patch, and currently is ignored by the tests.

Reviewers: dexonsmith, joker.eph, davidxl

Subscribers: tobiasvk, tejohnson, llvm-commits

Differential Revision: http://reviews.llvm.org/D13515

llvm-svn: 251837
2015-11-02 21:39:10 +00:00
Teresa Johnson bc11ede2c9 Fix test check label.
Summary:
I noticed when manually modifying this test that it was passing when I
expected it to fail. Looks like the combination of LABEL and NOT on the
check does not work. This can also be seen when running FileCheck with
only that one -check-prefix (removing the additional -check-prefix=B):

/usr/local/google/home/tejohnson/llvm/llvm_11_build/./bin/llvm-link -S -internalize -only-needed /usr/local/google/home/tejohnson/llvm/llvm_11_build/test/Linker/Output/link-flags.ll.tmp.b.bc /usr/local/google/home/tejohnson/llvm/llvm_11_build/test/Linker/Output/link-flags.ll.tmp.c.bc | /usr/local/google/home/tejohnson/llvm/llvm_11_build/./bin/FileCheck /usr/local/google/home/tejohnson/llvm/llvm_11/test/Linker/link-flags.ll -check-prefix=CN
error: no check strings found with prefix 'CN:'

The CN prefix checks don't in fact need "LABEL" so remove that.

Reviewers: tra

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14173

llvm-svn: 251655
2015-10-29 21:24:38 +00:00
Mehdi Amini d178f4fc89 Make the default triple optional by allowing an empty string
When building LLVM as a (potentially dynamic) library that can be linked against
by multiple compilers, the default triple is not really meaningful.
We allow to explicitely set it to an empty string when configuring LLVM.
In this case, said "target independent" tests in the test suite that are using
the default triple are disabled by matching the newly available feature
"default_triple".

Reviewers: probinson, echristo
Differential Revision: http://reviews.llvm.org/D12660

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 247775
2015-09-16 05:34:32 +00:00
David Blaikie 2f40830dde [opaque pointer type] Add textual IR support for explicit type parameter for global aliases
update.py:
import fileinput
import sys
import re

alias_match_prefix = r"(.*(?:=|:|^)\s*(?:external |)(?:(?:private|internal|linkonce|linkonce_odr|weak|weak_odr|common|appending|extern_weak|available_externally) )?(?:default |hidden |protected )?(?:dllimport |dllexport )?(?:unnamed_addr |)(?:thread_local(?:\([a-z]*\))? )?alias"
plain = re.compile(alias_match_prefix + r" (.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|addrspacecast|\[\[[a-zA-Z]|\{\{).*$)")
cast  = re.compile(alias_match_prefix + r") ((?:bitcast|inttoptr|addrspacecast)\s*\(.* to (.*?)(| addrspace\(\d+\) *)\*\)\s*(?:;.*)?$)")
gep   = re.compile(alias_match_prefix + r") ((?:getelementptr)\s*(?:inbounds)?\s*\((?P<type>.*), (?P=type)(?:\s*addrspace\(\d+\)\s*)?\* .*\)\s*(?:;.*)?$)")

def conv(line):
  m = re.match(cast, line)
  if m:
    return m.group(1) + " " + m.group(3) + ", " + m.group(2)
  m = re.match(gep, line)
  if m:
    return m.group(1) + " " + m.group(3) + ", " + m.group(2)
  m = re.match(plain, line)
  if m:
    return m.group(1) + ", " + m.group(2) + m.group(3) + "*" + m.group(4) + "\n"
  return line

for line in sys.stdin:
  sys.stdout.write(conv(line))

apply.sh:
for name in "$@"
do
  python3 `dirname "$0"`/update.py < "$name" > "$name.tmp" && mv "$name.tmp" "$name"
  rm -f "$name.tmp"
done

The actual commands:
From llvm/src:
find test/ -name *.ll | xargs ./apply.sh
From llvm/src/tools/clang:
find test/ -name *.mm -o -name *.m -o -name *.cpp -o -name *.c | xargs -I '{}' ../../apply.sh "{}"
From llvm/src/tools/polly:
find test/ -name *.ll | xargs ./apply.sh

llvm-svn: 247378
2015-09-11 03:22:04 +00:00
Artem Belevich 020d4fb17f New bitcode linker flags:
-only-needed -- link in only symbols needed by destination module
-internalize -- internalize linked symbols

Differential Revision: http://reviews.llvm.org/D12459

llvm-svn: 246561
2015-09-01 17:55:55 +00:00
Duncan P. N. Exon Smith 814b8e91c7 DI: Require subprogram definitions to be distinct
As a follow-up to r246098, require `DISubprogram` definitions
(`isDefinition: true`) to be 'distinct'.  Specifically, add an assembler
check, a verifier check, and bitcode upgrading logic to combat testcase
bitrot after the `DIBuilder` change.

While working on the testcases, I realized that
test/Linker/subprogram-linkonce-weak-odr.ll isn't relevant anymore.  Its
purpose was to check for a corner case in PR22792 where two subprogram
definitions match exactly and share the same metadata node.  The new
verifier check, requiring that subprogram definitions are 'distinct',
precludes that possibility.

I updated almost all the IR with the following script:

    git grep -l -E -e '= !DISubprogram\(.* isDefinition: true' |
    grep -v test/Bitcode |
    xargs sed -i '' -e 's/= \(!DISubprogram(.*, isDefinition: true\)/= distinct \1/'

Likely some variant of would work for out-of-tree testcases.

llvm-svn: 246327
2015-08-28 20:26:49 +00:00
Paul Robinson 78046b49a9 Make DW_AT_[MIPS_]linkage_name optional, and off by default for SCE.
Mangled "linkage" names can be huge, and if the debugger (or other
tools) have no use for them, the size savings can be very impressive
(on the order of 40%).

Add one test for controlling behavior, and modify a number of tests to
either stop using linkage names, or make llc emit them (so these tests
will still run when the default triple is for PS4).

Differential Revision: http://reviews.llvm.org/D11374

llvm-svn: 244678
2015-08-11 21:36:45 +00:00
Duncan P. N. Exon Smith 706f37e8df Linker: Fix references to uniqued nodes after r243883
r243883 started moving 'distinct' nodes instead of duplicated them in
lib/Linker.  This had the side-effect of sometimes not cloning uniqued
nodes that reference them.  I missed a corner case:

    !named = !{!0}
    !0 = !{!1}
    !1 = distinct !{!0}

!0 is the entry point for "remapping", and a temporary clone (say,
!0-temp) is created and mapped in case we need to model a uniquing
cycle.

    Recursive descent into !1.  !1 is distinct, so we leave it alone,
    but update its operand to !0-temp.

Pop back out to !0.  Its only operand, !1, hasn't changed, so we don't
need to use !0-temp.  !0-temp goes out of scope, and we're finished
remapping, but we're left with:

    !named = !{!0}
    !0 = !{!1}
    !1 = distinct !{null} ; uh oh...

Previously, if !0 and !0-temp ended up with identical operands, then
!0-temp couldn't have been referenced at all.  Now that distinct nodes
don't get duplicated, that assumption is invalid.  We need to
!0-temp->replaceAllUsesWith(!0) before freeing !0-temp.

I found this while running an internal `-flto -g` bootstrap.  Strangely,
there was no case of this in the open source bootstrap I'd done before
commit...

llvm-svn: 243961
2015-08-04 06:42:31 +00:00
Mehdi Amini c8d5783114 Update test suite to make "ninja check" succeed without native backend builtin
Requires "native" feature in most places that were failing.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 243960
2015-08-04 06:32:54 +00:00
Duncan P. N. Exon Smith 55ca964e94 DI: Disallow uniquable DICompileUnits
Since r241097, `DIBuilder` has only created distinct `DICompileUnit`s.
The backend is liable to start relying on that (if it hasn't already),
so make uniquable `DICompileUnit`s illegal and automatically upgrade old
bitcode.  This is a nice cleanup, since we can remove an unnecessary
`DenseSet` (and the associated uniquing info) from `LLVMContextImpl`.

Almost all the testcases were updated with this script:

    git grep -e '= !DICompileUnit' -l -- test |
    grep -v test/Bitcode |
    xargs sed -i '' -e 's,= !DICompileUnit,= distinct !DICompileUnit,'

I imagine something similar should work for out-of-tree testcases.

llvm-svn: 243885
2015-08-03 17:26:41 +00:00
Duncan P. N. Exon Smith ed013cd221 DI: Remove DW_TAG_arg_variable and DW_TAG_auto_variable
Remove the fake `DW_TAG_auto_variable` and `DW_TAG_arg_variable` tags,
using `DW_TAG_variable` in their place Stop exposing the `tag:` field at
all in the assembly format for `DILocalVariable`.

Most of the testcase updates were generated by the following sed script:

    find test/ -name "*.ll" -o -name "*.mir" |
    xargs grep -l 'DILocalVariable' |
    xargs sed -i '' \
      -e 's/tag: DW_TAG_arg_variable, //' \
      -e 's/tag: DW_TAG_auto_variable, //'

There were only a handful of tests in `test/Assembly` that I needed to
update by hand.

(Note: a follow-up could change `DILocalVariable::DILocalVariable()` to
set the tag to `DW_TAG_formal_parameter` instead of `DW_TAG_variable`
(as appropriate), instead of having that logic magically in the backend
in `DbgVariable`.  I've added a FIXME to that effect.)

llvm-svn: 243774
2015-07-31 18:58:39 +00:00
Peter Collingbourne ea45d834e0 Linker: Do not expect comdat to exist in source module.
llvm-svn: 240341
2015-06-22 21:46:51 +00:00
Sunil Srivastava d79dfcbc37 Changed renaming of local symbols by inserting a dot vefore the numeric suffix.
One code change and several test changes to match that
details in http://reviews.llvm.org/D9481

llvm-svn: 237150
2015-05-12 16:47:30 +00:00
Duncan P. N. Exon Smith a9308c49ef IR: Give 'DI' prefix to debug info metadata
Finish off PR23080 by renaming the debug info IR constructs from `MD*`
to `DI*`.  The last of the `DIDescriptor` classes were deleted in
r235356, and the last of the related typedefs removed in r235413, so
this has all baked for about a week.

Note: If you have out-of-tree code (like a frontend), I recommend that
you get everything compiling and tests passing with the *previous*
commit before updating to this one.  It'll be easier to keep track of
what code is using the `DIDescriptor` hierarchy and what you've already
updated, and I think you're extremely unlikely to insert bugs.  YMMV of
course.

Back to *this* commit: I did this using the rename-md-di-nodes.sh
upgrade script I've attached to PR23080 (both code and testcases) and
filtered through clang-format-diff.py.  I edited the tests for
test/Assembler/invalid-generic-debug-node-*.ll by hand since the columns
were off-by-three.  It should work on your out-of-tree testcases (and
code, if you've followed the advice in the previous paragraph).

Some of the tests are in badly named files now (e.g.,
test/Assembler/invalid-mdcompositetype-missing-tag.ll should be
'dicompositetype'); I'll come back and move the files in a follow-up
commit.

llvm-svn: 236120
2015-04-29 16:38:44 +00:00
Duncan P. N. Exon Smith c8d987b121 Linker: Copy over function metadata attachments
Update `lib/Linker` to handle `Function` metadata attachments.  The
attachments stick with the function body.

llvm-svn: 235786
2015-04-24 22:07:31 +00:00
Duncan P. N. Exon Smith 085f80536f Linker: Update -override testcase to check callers
Check that `@main` is calling `@foo2` (the renamed internal function),
not the `@foo` with external linkage that's been pulled in from the
override file.

llvm-svn: 235730
2015-04-24 16:56:24 +00:00
Duncan P. N. Exon Smith e868123d8f Linker: Add flag to override linkage rules
Add a flag to lib/Linker (and `llvm-link`) to override linkage rules.
When set, the functions in the source module *always* replace those in
the destination module.

The `llvm-link` option is `-override=abc.ll`.  All the "regular" modules
are loaded and linked first, followed by the `-override` modules.  This
is useful for debugging workflows where some subset of the module (e.g.,
a single function) is extracted into a separate file where it's
optimized differently, before being merged back in.

Patch by Luqman Aden!

llvm-svn: 235473
2015-04-22 04:11:00 +00:00
David Blaikie 23af64846f [opaque pointer type] Add textual IR support for explicit type parameter to the call instruction
See r230786 and r230794 for similar changes to gep and load
respectively.

Call is a bit different because it often doesn't have a single explicit
type - usually the type is deduced from the arguments, and just the
return type is explicit. In those cases there's no need to change the
IR.

When that's not the case, the IR usually contains the pointer type of
the first operand - but since typed pointers are going away, that
representation is insufficient so I'm just stripping the "pointerness"
of the explicit type away.

This does make the IR a bit weird - it /sort of/ reads like the type of
the first operand: "call void () %x(" but %x is actually of type "void
()*" and will eventually be just of type "ptr". But this seems not too
bad and I don't think it would benefit from repeating the type
("void (), void () * %x(" and then eventually "void (), ptr %x(") as has
been done with gep and load.

This also has a side benefit: since the explicit type is no longer a
pointer, there's no ambiguity between an explicit type and a function
that returns a function pointer. Previously this case needed an explicit
type (eg: a function returning a void() function was written as
"call void () () * @x(" rather than "call void () * @x(" because of the
ambiguity between a function returning a pointer to a void() function
and a function returning void).

No ambiguity means even function pointer return types can just be
written alone, without writing the whole function's type.

This leaves /only/ the varargs case where the explicit type is required.

Given the special type syntax in call instructions, the regex-fu used
for migration was a bit more involved in its own unique way (as every
one of these is) so here it is. Use it in conjunction with the apply.sh
script and associated find/xargs commands I've provided in rr230786 to
migrate your out of tree tests. Do let me know if any of this doesn't
cover your cases & we can iterate on a more general script/regexes to
help others with out of tree tests.

About 9 test cases couldn't be automatically migrated - half of those
were functions returning function pointers, where I just had to manually
delete the function argument types now that we didn't need an explicit
function type there. The other half were typedefs of function types used
in calls - just had to manually drop the * from those.

import fileinput
import sys
import re

pat = re.compile(r'((?:=|:|^|\s)call\s(?:[^@]*?))(\s*$|\s*(?:(?:\[\[[a-zA-Z0-9_]+\]\]|[@%](?:(")?[\\\?@a-zA-Z0-9_.]*?(?(3)"|)|{{.*}}))(?:\(|$)|undef|inttoptr|bitcast|null|asm).*$)')
addrspace_end = re.compile(r"addrspace\(\d+\)\s*\*$")
func_end = re.compile("(?:void.*|\)\s*)\*$")

def conv(match, line):
  if not match or re.search(addrspace_end, match.group(1)) or not re.search(func_end, match.group(1)):
    return line
  return line[:match.start()] + match.group(1)[:match.group(1).rfind('*')].rstrip() + match.group(2) + line[match.end():]

for line in sys.stdin:
  sys.stdout.write(conv(re.search(pat, line), line))

llvm-svn: 235145
2015-04-16 23:24:18 +00:00
Duncan P. N. Exon Smith 4628282fac tools: Unify how verifyModule() is called
Unify the error messages for the various tools when `verifyModule()`
fails on an input module.  The "brave new way" is:

    lltool: path/to/input.ll: error: input module is broken!

llvm-svn: 233667
2015-03-31 03:07:23 +00:00
Duncan P. N. Exon Smith ce2b983425 DebugInfo: Fix testcases with invalid MDSubprogram nodes
Fix testcases that don't pass the verifier after a WIP patch to check
`MDSubprogram` operands more effectively.  I found the following issues:

  - When `isDefinition: false`, the `variables:` field might point at
    `!{i32 786468}`, or at a tuple that pointed at an empty tuple with
    the comment "previously: invalid DW_TAG_base_type" (I vaguely recall
    adding those comments during an upgrade script).  In these cases, I
    just dropped the array.
  - The `variables:` field might point at something like `!{!{!8}}`,
    where `!8` was an `MDLocation`.  I removed the extra layer of
    indirection.
  - Invalid `type:` (not an `MDSubroutineType`).

llvm-svn: 233466
2015-03-28 02:26:45 +00:00
Duncan P. N. Exon Smith 988a7f8b79 DebugInfo: Fix bad debug info for compile units and types
Fix debug info in these tests, which started failing with a WIP patch to
verify compile units and types.  The problems look like they were all
caused by bitrot.  They fell into these categories:

  - Using `!{i32 0}` instead of `!{}`.
  - Using `!{null}` instead of `!{}`.
  - Using `!MDExpression()` instead of `!{}`.
  - Using `!8` instead of `!{!8}`.
  - `file:` references that pointed at `MDCompileUnit`s instead of the
    same `MDFile` as the compile unit.
  - `file:` references that were numerically off-by-one or (off-by-ten).

llvm-svn: 233415
2015-03-27 20:46:33 +00:00
Rafael Espindola 2fcfb5e5c7 Work around pr23045 and make it easier to reproduce.
Dropping old debug format requires the entire module to be read upfront.

This was failing only with the gold plugin, but that is just because
llvm-link was not upgrading metadata.

The new testcase using llvm-link shows the problem.

llvm-svn: 233381
2015-03-27 15:55:06 +00:00
Yaron Keren 39972f7723 Fix subprogram-linkonce-weak.ll and subprogram-linkonce-weak-odr.ll for Windows.
llvm-svn: 233375
2015-03-27 13:52:12 +00:00
Duncan P. N. Exon Smith 264899823f Verifier: Check accessors of MDLocation
Check accessors of `MDLocation`, and change them to `cast<>` down to the
right types.  Also add type-safe factory functions.

All the callers that handle broken code need to use the new versions of
the accessors (`getRawScope()` instead of `getScope()`) that still
return `Metadata*`.  This is also necessary for things like
`MDNodeKeyImpl<MDLocation>` (in LLVMContextImpl.h) that need to unique
the nodes when their operands might still be forward references of the
wrong type.

In the `Value` hierarchy, consumers that handle broken code use
`getOperand()` directly.  However, debug info nodes have a ton of
operands, and their order (even their existence) isn't stable yet.  It's
safer and more maintainable to add an explicit "raw" accessor on the
class itself.

llvm-svn: 233322
2015-03-26 22:05:04 +00:00
Duncan P. N. Exon Smith c947892d10 Reapply "Linker: Drop function pointers for overridden subprograms"
This reverts commit r233254, effectively reapplying r233164 (and its
successors), with an additional testcase for when subprograms match
exactly.  This fixes PR22792 (again).

I'm using the same approach, but I've moved up the call to
`stripReplacedSubprograms()`.  The function pointers need to be dropped
before mapping any metadata from the source module, or else this can
drop the function from new subprograms that have merged (via Metadata
uniquing) with the old ones.  Dropping the pointers first prevents them
from merging.

**** The original commit message follows. ****

Linker: Drop function pointers for overridden subprograms

Instead of dropping subprograms that have been overridden, just set
their function pointers to `nullptr`.  This is a minor adjustment to the
stop-gap fix for PR21910 committed in r224487, and fixes the crasher
from PR22792.

The problem that r224487 put a band-aid on: how do we find the canonical
subprogram for a `Function`?  Since the backend currently relies on
`DebugInfoFinder` (which does a naive in-order traversal of compile
units and picks the first subprogram) for this, r224487 tried dropping
non-canonical subprograms.

Dropping subprograms fails because the backend *also* builds up a map
from subprogram to compile unit (`DwarfDebug::SPMap`) based on the
subprogram lists.  A missing subprogram causes segfaults later when an
inlined reference (such as in this testcase) is created.

Instead, just drop the `Function` pointer to `nullptr`, which nicely
mirrors what happens when an already-inlined `Function` is optimized
out.  We can't really be sure that it's the same definition anyway, as
the testcase demonstrates.

This still isn't completely satisfactory.  Two flaws at least that I can
think of:

  - I still haven't found a straightforward way to make this symmetric
    in the IR.  (Interestingly, the DWARF output is already symmetric,
    and I've tested for that to be sure we don't regress.)
  - Using `DebugInfoFinder` to find the canonical subprogram for a
    function is kind of crazy.  We should just attach metadata to the
    function, like this:

        define weak i32 @foo(i32, i32) !dbg !MDSubprogram(...) {

llvm-svn: 233302
2015-03-26 18:35:30 +00:00
Duncan P. N. Exon Smith 7124230682 Revert "Linker: Drop function pointers for overridden subprograms"
This reverts commit r233164 and its testcase follow-ups in r233165,
r233207, r233214, and r233221.  It apparently unleashed an LTO bootstrap
failure, at least on Darwin:

http://lab.llvm.org:8080/green/job/clang-stage2-configure-Rlto_build/3376/

I'm reproducing now.

llvm-svn: 233254
2015-03-26 05:27:45 +00:00
Duncan P. N. Exon Smith 041ceb7d57 llvm-link: Verify input modules
Otherwise, broken input modules can cause assertions.  I've updated two
of the testcases that started failing (modules that had `Require` flags
but didn't meet their own requirements), but Rafael and I decided that
test/Linker/2011-08-22-ResolveAlias.ll should just be deleted outright
-- it's a leftover of the way llvm-gcc used to implement weakref.

llvm-svn: 233229
2015-03-25 23:22:10 +00:00
Duncan P. N. Exon Smith bb2958a042 Linker: Stop using -gmlt test/Linker/subprogram-linkonce-weak.ll
As dblaikie pointed out, if I stop setting `emissionKind: 2` then the
backend won't do magical things on Linux vs. Darwin.  I had wrongly
assumed that there were stricter requirements on the input if we weren't
in line-tables-only mode, but apparently not.

With that knowledge, clean up this testcase a little more.

  - Set `emissionKind: 1`.
  - Add back checks for the weak version of @foo.
  - Check more robustly that we have the right subprograms by checking
    the `DW_AT_decl_file` and `DW_AT_decl_line` which now show up.
  - Check the line table in isolation (since it's no longer doubling as
    an indirect test for the subprogram of the weak version of @foo).

llvm-svn: 233221
2015-03-25 21:36:41 +00:00
Duncan P. N. Exon Smith c6d5cfe162 Linker: Loosen checks slightly from r233207
According to at least one bot [1], function prologues aren't always
empty for these functions.  Skip that part of the follow-up check.

llvm-svn: 233214
2015-03-25 20:51:21 +00:00
Duncan P. N. Exon Smith f9dc7036d3 Linker: Rewrite dwarfdump checks from r233164
Rewrite the checks from r233164 that I temporarily disabled in r233165.

It turns out that the line-tables only debug info we emit from `llc` is
(intentionally) different on Linux than on Darwin.  r218129 started
skipping emission of subprograms with no inlined subroutines, and
r218702 was a spiritual revert of that behaviour for Darwin.

I think we can still test this in a platform-neutral way.

  - Stop checking for the possibly missing `DW_TAG_subprogram` defining
    the debug info for the real version of `@foo`.
  - Start checking the line tables, ensuring that the right debug info
    was used to generate them (grabbing `DW_AT_low_pc` from the compile
    unit).
  - I changed up the line numbers used in the "weak" version so it's
    easier to follow.

This should hopefully finish off PR22792.

llvm-svn: 233207
2015-03-25 19:57:42 +00:00
Duncan P. N. Exon Smith 419d523d62 Linker: Temporarily disable dwarfdump checks from r233164
At least one Linux bot [1] doesn't like my dwarfdump checks, so I've
disable those until I can investigate what's going on there.  I'll
continue to track this in PR22792.

[1]: http://bb.pgr.jp/builders/cmake-llvm-x86_64-linux/builds/22863

llvm-svn: 233165
2015-03-25 02:43:04 +00:00
Duncan P. N. Exon Smith 004ced3b08 Linker: Drop function pointers for overridden subprograms
Instead of dropping subprograms that have been overridden, just set
their function pointers to `nullptr`.  This is a minor adjustment to the
stop-gap fix for PR21910 committed in r224487, and fixes the crasher
from PR22792.

The problem that r224487 put a band-aid on: how do we find the canonical
subprogram for a `Function`?  Since the backend currently relies on
`DebugInfoFinder` (which does a naive in-order traversal of compile
units and picks the first subprogram) for this, r224487 tried dropping
non-canonical subprograms.

Dropping subprograms fails because the backend *also* builds up a map
from subprogram to compile unit (`DwarfDebug::SPMap`) based on the
subprogram lists.  A missing subprogram causes segfaults later when an
inlined reference (such as in this testcase) is created.

Instead, just drop the `Function` pointer to `nullptr`, which nicely
mirrors what happens when an already-inlined `Function` is optimized
out.  We can't really be sure that it's the same definition anyway, as
the testcase demonstrates.

This still isn't completely satisfactory.  Two flaws at least that I can
think of:

  - I still haven't found a straightforward way to make this symmetric
    in the IR.  (Interestingly, the DWARF output is already symmetric,
    and I've tested for that to be sure we don't regress.)
  - Using `DebugInfoFinder` to find the canonical subprogram for a
    function is kind of crazy.  We should just attach metadata to the
    function, like this:

        define weak i32 @foo(i32, i32) !dbg !MDSubprogram(...) {

llvm-svn: 233164
2015-03-25 02:26:32 +00:00
David Blaikie f72d05bc7b [opaque pointer type] Add textual IR support for explicit type parameter to gep operator
Similar to gep (r230786) and load (r230794) changes.

Similar migration script can be used to update test cases, which
successfully migrated all of LLVM and Polly, but about 4 test cases
needed manually changes in Clang.

(this script will read the contents of stdin and massage it into stdout
- wrap it in the 'apply.sh' script shown in previous commits + xargs to
apply it over a large set of test cases)

import fileinput
import sys
import re

rep = re.compile(r"(getelementptr(?:\s+inbounds)?\s*\()((<\d*\s+x\s+)?([^@]*?)(|\s*addrspace\(\d+\))\s*\*(?(3)>)\s*)(?=$|%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|zeroinitializer|<|\[\[[a-zA-Z]|\{\{)", re.MULTILINE | re.DOTALL)

def conv(match):
  line = match.group(1)
  line += match.group(4)
  line += ", "
  line += match.group(2)
  return line

line = sys.stdin.read()
off = 0
for match in re.finditer(rep, line):
  sys.stdout.write(line[off:match.start()])
  sys.stdout.write(conv(match))
  off = match.end()
sys.stdout.write(line[off:])

llvm-svn: 232184
2015-03-13 18:20:45 +00:00
Paul Robinson 857b4434df Emit correct linkage-name attribute based on DWARF version.
There are still 4 tests that check for DW_AT_MIPS_linkage_name,
because they specify DWARF 2 or 3 in the module metadata. So, I didn't
create an explicit version-based test for the attribute.

Differential Revision: http://reviews.llvm.org/D8227

llvm-svn: 231880
2015-03-10 22:44:45 +00:00
Rafael Espindola a5b9e1cf39 Remember to move a type to the correct set when setting the body.
We would set the body of a struct type (therefore making it non-opaque)
but were forgetting to move it to the non-opaque set.

Fixes pr22807.

llvm-svn: 231442
2015-03-06 00:50:21 +00:00
Mehdi Amini 46a43556db Make DataLayout Non-Optional in the Module
Summary:
DataLayout keeps the string used for its creation.

As a side effect it is no longer needed in the Module.
This is "almost" NFC, the string is no longer
canonicalized, you can't rely on two "equals" DataLayout
having the same string returned by getStringRepresentation().

Get rid of DataLayoutPass: the DataLayout is in the Module

The DataLayout is "per-module", let's enforce this by not
duplicating it more than necessary.
One more step toward non-optionality of the DataLayout in the
module.

Make DataLayout Non-Optional in the Module

Module->getDataLayout() will never returns nullptr anymore.

Reviewers: echristo

Subscribers: resistor, llvm-commits, jholewinski

Differential Revision: http://reviews.llvm.org/D7992

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 231270
2015-03-04 18:43:29 +00:00
Duncan P. N. Exon Smith e274180f0e DebugInfo: Move new hierarchy into place
Move the specialized metadata nodes for the new debug info hierarchy
into place, finishing off PR22464.  I've done bootstraps (and all that)
and I'm confident this commit is NFC as far as DWARF output is
concerned.  Let me know if I'm wrong :).

The code changes are fairly mechanical:

  - Bumped the "Debug Info Version".
  - `DIBuilder` now creates the appropriate subclass of `MDNode`.
  - Subclasses of DIDescriptor now expect to hold their "MD"
    counterparts (e.g., `DIBasicType` expects `MDBasicType`).
  - Deleted a ton of dead code in `AsmWriter.cpp` and `DebugInfo.cpp`
    for printing comments.
  - Big update to LangRef to describe the nodes in the new hierarchy.
    Feel free to make it better.

Testcase changes are enormous.  There's an accompanying clang commit on
its way.

If you have out-of-tree debug info testcases, I just broke your build.

  - `upgrade-specialized-nodes.sh` is attached to PR22564.  I used it to
    update all the IR testcases.
  - Unfortunately I failed to find way to script the updates to CHECK
    lines, so I updated all of these by hand.  This was fairly painful,
    since the old CHECKs are difficult to reason about.  That's one of
    the benefits of the new hierarchy.

This work isn't quite finished, BTW.  The `DIDescriptor` subclasses are
almost empty wrappers, but not quite: they still have loose casting
checks (see the `RETURN_FROM_RAW()` macro).  Once they're completely
gutted, I'll rename the "MD" classes to "DI" and kill the wrappers.  I
also expect to make a few schema changes now that it's easier to reason
about everything.

llvm-svn: 231082
2015-03-03 17:24:31 +00:00
Reid Kleckner 02ec6a3ec3 lit: Add 'cd' support to the internal shell and port some tests
The internal shell was already threading around a 'cwd' parameter. We
just have to make it mutable so that we can update it as the test script
executes.

If the shell ever grows support for environment variable substitution,
we could also implement support for export.

llvm-svn: 231017
2015-03-02 21:33:18 +00:00
David Blaikie a79ac14fa6 [opaque pointer type] Add textual IR support for explicit type parameter to load instruction
Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)

import fileinput
import sys
import re

pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")

for line in sys.stdin:
  sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7649

llvm-svn: 230794
2015-02-27 21:17:42 +00:00
David Blaikie 79e6c74981 [opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction
One of several parallel first steps to remove the target type of pointers,
replacing them with a single opaque pointer type.

This adds an explicit type parameter to the gep instruction so that when the
first parameter becomes an opaque pointer type, the type to gep through is
still available to the instructions.

* This doesn't modify gep operators, only instructions (operators will be
  handled separately)

* Textual IR changes only. Bitcode (including upgrade) and changing the
  in-memory representation will be in separate changes.

* geps of vectors are transformed as:
    getelementptr <4 x float*> %x, ...
  ->getelementptr float, <4 x float*> %x, ...
  Then, once the opaque pointer type is introduced, this will ultimately look
  like:
    getelementptr float, <4 x ptr> %x
  with the unambiguous interpretation that it is a vector of pointers to float.

* address spaces remain on the pointer, not the type:
    getelementptr float addrspace(1)* %x
  ->getelementptr float, float addrspace(1)* %x
  Then, eventually:
    getelementptr float, ptr addrspace(1) %x

Importantly, the massive amount of test case churn has been automated by
same crappy python code. I had to manually update a few test cases that
wouldn't fit the script's model (r228970,r229196,r229197,r229198). The
python script just massages stdin and writes the result to stdout, I
then wrapped that in a shell script to handle replacing files, then
using the usual find+xargs to migrate all the files.

update.py:
import fileinput
import sys
import re

ibrep = re.compile(r"(^.*?[^%\w]getelementptr inbounds )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")
normrep = re.compile(       r"(^.*?[^%\w]getelementptr )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")

def conv(match, line):
  if not match:
    return line
  line = match.groups()[0]
  if len(match.groups()[5]) == 0:
    line += match.groups()[2]
  line += match.groups()[3]
  line += ", "
  line += match.groups()[1]
  line += "\n"
  return line

for line in sys.stdin:
  if line.find("getelementptr ") == line.find("getelementptr inbounds"):
    if line.find("getelementptr inbounds") != line.find("getelementptr inbounds ("):
      line = conv(re.match(ibrep, line), line)
  elif line.find("getelementptr ") != line.find("getelementptr ("):
    line = conv(re.match(normrep, line), line)
  sys.stdout.write(line)

apply.sh:
for name in "$@"
do
  python3 `dirname "$0"`/update.py < "$name" > "$name.tmp" && mv "$name.tmp" "$name"
  rm -f "$name.tmp"
done

The actual commands:
From llvm/src:
find test/ -name *.ll | xargs ./apply.sh
From llvm/src/tools/clang:
find test/ -name *.mm -o -name *.m -o -name *.cpp -o -name *.c | xargs -I '{}' ../../apply.sh "{}"
From llvm/src/tools/polly:
find test/ -name *.ll | xargs ./apply.sh

After that, check-all (with llvm, clang, clang-tools-extra, lld,
compiler-rt, and polly all checked out).

The extra 'rm' in the apply.sh script is due to a few files in clang's test
suite using interesting unicode stuff that my python script was throwing
exceptions on. None of those files needed to be migrated, so it seemed
sufficient to ignore those cases.

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7636

llvm-svn: 230786
2015-02-27 19:29:02 +00:00
Akira Hatanaka 59f3073d23 Add run line that was missing in r228999.
Also, change the run lines to use -allow-empty.

llvm-svn: 229118
2015-02-13 16:00:03 +00:00
Akira Hatanaka c43df5187c [LinkModules] Change the way ModuleLinker merges triples.
This commit makes the following changes:

- Stop issuing a warning when the triples' string representations do not match
  exactly if the Triple objects generated from the strings compare equal.
 
- On Apple platforms, choose the triple that has the larger minimum version
  number. 

rdar://problem/16743513

Differential Revision: http://reviews.llvm.org/D7591

llvm-svn: 228999
2015-02-13 00:40:41 +00:00
Duncan P. N. Exon Smith 920df5c1bb Utils: Resolve cycles under distinct MDNodes
Track unresolved nodes under distinct `MDNode`s during `MapMetadata()`,
and resolve them at the end.  Previously, these cycles wouldn't get
resolved.

llvm-svn: 228180
2015-02-04 19:44:34 +00:00
Duncan P. N. Exon Smith 9885469922 IR: Move MDLocation into place
This commit moves `MDLocation`, finishing off PR21433.  There's an
accompanying clang commit for frontend testcases.  I'll attach the
testcase upgrade script I used to PR21433 to help out-of-tree
frontends/backends.

This changes the schema for `DebugLoc` and `DILocation` from:

    !{i32 3, i32 7, !7, !8}

to:

    !MDLocation(line: 3, column: 7, scope: !7, inlinedAt: !8)

Note that empty fields (line/column: 0 and inlinedAt: null) don't get
printed by the assembly writer.

llvm-svn: 226048
2015-01-14 22:27:36 +00:00
Duncan P. N. Exon Smith a5a0f5766a Utils: Handle remapping distinct MDLocations
Part of PR21433.

llvm-svn: 225921
2015-01-14 01:29:32 +00:00
Duncan P. N. Exon Smith 47d82981d6 Utils: Add mapping for uniqued MDLocations
Still doesn't handle distinct ones.  Part of PR21433.

llvm-svn: 225914
2015-01-14 01:20:27 +00:00